Not understand line of code

#1

in the code what the meaning of (return ) and what the significance of writing it the code

#2

return is use to stop further execution of lines in a function

when you write return it will leave the current function and goes there from where it is called

significance in context of video
if n==0 you need not to do anything
you doesn’t require to execute further lines so we use return
here it work as base case(where you want to stop recursive calls)

i hope this help
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